Ray tracing without Nvidia

Nvidia shook up the CG community last Fall at Siggraph when the company introduced its RTX Turing-based AIBs that are capable of real-time ray tracing (RTRT). Microsoft brought out a special API for it, DXR, and several ISVs committed to it (see article this issue, Ray tracing is a journey ).  All of that was and still is, exciting. I have played all the RTRT games and loved them. Their engagement of ray tracing varied, but that’s only because it is early days, and in cases, it was a proof of concept patch. Nvidia was, is, way out front with